Make a working solution by mixing 1 part A with 2 parts B with 100 parts water. To make 1 liter of
working solution add 10 ml of A and 20 ml of B to 1000 ml of distilled water. This high-acutance developer produces superior gradation for fine art work.

Make a working solution by mixing 2 parts A with 8 parts B with 100 parts water. This pyro
solution is specially designed as a substitute for PMK and provides even development with tube processors running at 25 rpm. Developing times range from 5 to 7 minutes.

Mix 40 milliliters of A and 100 milliliters of B with 1000 milliliters of distilled water to make a
working solution. This highly compensating formula causes a speed loss of at least a full stop, but allows the film to capture approximately a 14-stop range.

To make a standard working solution, mix 1 part A with 1 part B with 100 ml water. Pyrocat-HD is not subject to problems with uneven development, so agitation can be reduced to once
per minute or less. 2.5 grams of Metol may be substituted for the Phenidone.

One of the few hydroquinone-only formulae. Said to give brown tones on Agfa Portriga (1:4) and warm black tones on Agfa Brovira (1:5). ”The
Ansco 120 formula above is often referred to in formularies as Agfa 120.

Also known as Dassonville D-3, and nearly identical to Edwal 106. Dilute 1:3 for use.
Develop 2.5 to 3 minutes. May be used at dilutions as high as 1:7 or 1:15 for brown tones, with developing times of 3 to 10 minutes.

For use normal use, mix 1/4 ounce (7.5 ml) of solution A with 6 ounces (180 ml) of solution B and add water to make 16 ounces or 500
ml. This solution works quickly, so reduction must be carefully monitored. For a slower reducing action, increase the amount of water or reduce the amount of Solution A.

Add 125 ml of Solution No. 2 slowly to Solution No.1
while stirring the latter rapidly. After mixing, the bath should not be used until it has become cool and has formed a sediment. Sediment formation may continue for several days or a week.
Pour off the clear liquid for use. Add the clear solution to a tray standing in a water bath and heat the solution to 110º. Dry prints should be soaked thoroughly in water before
toning. Keep an untoned print at hand for comparison purposes. Chloride papers should be toned between 100º and 110º Farenheit for 5 to 20 minutes. Most modern papers seem to
require about 20 minutes. After 50 8x10 inch prints have been toned, add 4 ml of Stock Solution No. 2 to the toner mixture.

Prints should be developed a little lighter than usual for this toner.
Solutions should be prepared 24 hours before use and mixed in equal parts immediately before use. Toning takes about 5 minutes. Wash thoroughly.

Handle sodium hydroxide with extreme care. Wear gloves and eye protection. Add the hydroxide very slowly to the cold water, while stirring, as
it will generate a great deal of heat and may boil if added too quickly.

Instructions: Reduce the prints in the reducing bath until no trace of black remains. 1-2 minutes is usually
sufficient. Wash thoroughly until all the yellow has been cleared. Redevelop.

* In regard to the chemical nature of sodium bisulfite see theJournal of Chemical Education, 2003, 80, 1482 or 2000, 77, 830.

Note: If you are not familiar with handling photographic chemicals, please take the time to educate yourself before using unfamiliar
products. Some safety information may be found in my article on Mixing Developers. More detailed safety information may be found in Photographic Processing Hazards.